Common problems in putty powder

A common problem in putty powders is that they dry quickly. This is mainly due to the amount of calcium ash powder added (too large, the amount of calcium calcium powder used in the putty formula can be appropriately reduced, which is related to the water retention rate of the fiber, and also to the dryness of the wall; peeling and rolling. This is related to water retention The low viscosity of cellulose is prone to this situation or the amount of addition is small; the powder removal of the interior wall putty powder. This is related to the amount of ash calcium powder (the amount of ash calcium powder in the putty formula is too small or the purity of the ash calcium powder If it is too low, it is related to appropriately increasing the amount of ash calcium powder in the putty powder formula, and it is also related to the amount and quality of cellulose, which is reflected in the water retention rate of the product. The calcium oxide in the calcium hydroxide is not fully converted to calcium hydroxide, which is caused by insufficient hydration time; foaming. This is related to the dry humidity and flatness of the wall, and it is also related to the construction; pinpoints appear. This is related to It is related to cellulose, its film-forming property is poor, and the impurities in cellulose react slightly with ash calcium. If the reaction is severe, the putty powder will be in a state. It cannot be put on the wall, and it has no cohesive force. In addition, the fiber This situation also occurs in products that have been mixed with carboxymethyl groups in the element; volcanoes and fires appear. This is obviously related to the water surface tension of the hydroxypropyl methylcellulose aqueous solution. The water surface tension of the hydroxyethyl aqueous solution is not obvious. Finishing treatment will be good; the putty is easy to crack and turn yellow after drying. This is related to the addition of a large amount of ash calcium powder. If the amount of ash calcium powder is too much, the hardness of the putty powder will increase after drying. Only the hardness is not It is easy to crack when it is flexible, especially when it is subjected to external force. It is also related to the high content of calcium oxide in ash calcium powder.

Coarse fineness is not only wasteful, but also reduces the local strength of the mortar. When such a dry powder mortar is constructed in a large area, the curing speed of the local dry powder mortar will be significantly reduced, and cracks will appear due to different curing times. For the sprayed mortar with mechanical construction, the requirement for fineness is higher due to the shorter mixing time. The fineness of cellulose also has a certain impact on its water retention. Generally speaking, for methyl cellulose ethers with the same viscosity but different fineness, in the case of the same addition amount, the finer the finer the better the water retention effect.